+ Error stacktraces are turned on.
[INFO]
Scanning for projects...
[INFO]
Searching repository for plugin with prefix: 'dependency'.
[INFO]
------------------------------------------------------------------------
[INFO]
Building Maven Default Project
[INFO]
task-segment: [dependency:tree]
[INFO]
------------------------------------------------------------------------
[INFO]
------------------------------------------------------------------------
[ERROR]
BUILD ERROR
[INFO]
------------------------------------------------------------------------
[INFO] Cannot
execute mojo: tree. It requires a project with an existing pom.xml, but the
build is not using one.
[INFO]
------------------------------------------------------------------------
[INFO]
Trace
org.apache.maven.lifecycle.LifecycleExecutionException:
Cannot execute mojo: tree. It requires a project with an existing pom.xml, but
the build is not using one.
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:719)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
at
org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
at
org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
Caused
by: org.apache.maven.plugin.MojoExecutionException: Cannot execute mojo: tree.
It requires a project with an existing pom.xml, but the build is not using
one.
at
org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:414)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
... 17 more
[INFO]
------------------------------------------------------------------------
[INFO]
Total time: 1 second
[INFO]
Finished at: Wed Jun 26 02:38:57 EDT 2013
[INFO]
Final Memory: 3M/61M
[INFO]
------------------------------------------------------------------------

Normally
this error happens, when you try to run the mvn dependency:tree command
from a location, where it does not find a POM.mvn
dependency:tree is used to see/verify the dependency between jars used in a
particular project.
So,
the solution is :
navigate
to your project directory and where you have the pom.xml file for the project
you want to verify the jar dependencies:
For
example, like